Schizoaffective disorder: symptoms, causes, diagnosis and treatment

Schizoaffective disorder is a severe mental illness. The Royal College of Psychiatrists says people who live with it can experience extreme differences in the way they perceive the world, find it hard to tell what is real, and also have extreme and distressing changes in mood.

The name explains the condition: "schizo" relates to the symptoms of psychosis and "affective" relates to mood. The College describes it as sitting in the spectrum of schizophrenia and bipolar disorder, because it has equally prominent psychotic symptoms and mood symptoms.

Rethink Mental Illness says it is less common than schizophrenia and that accurate figures for how many people are affected are hard to find. It is unlikely that a person has all the symptoms all the time. The College explains that different symptoms appear at different times and are more or less severe depending on a number of factors.

A person has psychotic symptoms and the mood symptoms of bipolar disorder (manic, mixed and depressive episodes). During an episode a person may find it difficult to realise they are unwell, which the College notes can make it hard to ask for help.

• Delusions: beliefs that feel completely real to the person but are not shared by others, such as believing they are being watched or harmed, or that they are extremely powerful or important.

• Hallucinations: hearing, seeing, feeling, smelling or tasting things other people do not. Hearing voices is the most common type.

• Disorganised thinking and speech, which others find confusing or hard to follow.

• Negative symptoms: showing less emotion, speaking less, lacking motivation, withdrawing from others, or being unable to look after yourself as you usually would.

• Depressive episodes: consistently low mood, loss of interest, poor concentration, changes in sleep and appetite, feeling worthless, guilty or hopeless, or thoughts of not wanting to be alive.

• Manic episodes: an unusually happy or irritable mood, being very active, speaking and thinking quickly, needing less sleep, being easily distracted and acting without thinking, such as spending money you do not have.

• Mixed episodes, where manic and depressive symptoms occur at the same time and can change from day to day.

The three conditions overlap, which is why a diagnosis can take time. The College says schizoaffective disorder and schizophrenia are different conditions that share some symptoms and treatments, and that the main difference is the mood component. Psychosis is a group of symptoms that can occur in many conditions, including schizophrenia, bipolar disorder and severe depression.

Psychiatrists do not know exactly what causes it. The College says it often involves several factors working together, and that many people with these risk factors never develop it, while some people develop it with none of them.

Genetic factors play a part. Both the College and Rethink say it is slightly more common when relatives have schizophrenia, schizoaffective disorder or bipolar disorder. The College states that if you have a parent with a severe mental illness, you have a 1 in 3 chance of developing a severe mental illness yourself. It also describes differences in brain structure and chemistry seen in some people.

Environmental factors include significant stress, such as bereavement or long-term difficulties at work or in family relationships, and abuse or neglect in childhood. The College says regular cannabis use seems to significantly increase the risk of psychotic symptoms, that stronger forms such as skunk may increase it further, particularly if use starts in the early teens, and that amphetamines and alcohol can also trigger psychotic symptoms.

The College is clear that, whatever the reason, developing schizoaffective disorder is not the person's fault.

A GP is the usual first step. The College says a GP will probably refer you to a specialist mental health service or to your local Early Intervention in Psychosis (EIP) service. A psychiatrist then carries out a mental health assessment. There is no physical test, so the assessor asks about symptoms, drug and alcohol use, medicines, physical health, relationships, past experiences and daily functioning.

Rethink explains that diagnosis uses the international classification systems (ICD-11 and DSM-5). Psychosis and mood symptoms should be clearly present for a number of weeks and not be explained by another condition, substance or medication. It may take more than one assessment, and the diagnosis can be confused with schizophrenia or bipolar disorder at first.

Psychosis itself has many possible causes, including brain injury, sleep deprivation, withdrawal from alcohol or drugs, infections that cause delirium and some medicines, so assessment includes ruling these out.

The aims, according to the College, are to reduce symptoms, relieve distress and disruption to daily life, and help the person regain quality of life. Because the condition combines symptoms of schizophrenia and mood disorders, Rethink explains that the treatments are those recommended for those conditions, following NICE guidance on psychosis and schizophrenia in adults and on bipolar disorder.

On medication, the College says all antipsychotics have been consistently shown to be similarly effective, apart from clozapine, which has been shown to be more effective. What varies is the side effects. Clozapine is suggested if at least two different antipsychotics have been tried for at least several weeks and psychotic symptoms still cause trouble. It comes with closer monitoring.

The College says the condition is treatable and that people with it can live full and happy lives. Medication choices are individual. It advises speaking to a doctor if side effects feel unpleasant rather than stopping a medicine alone, because a different medicine or dose can often be found.

People with the illness can experience worse physical health, particularly cardiovascular health, which is why yearly checks matter. The College says physical health monitoring tests should happen at least once a year while taking the medicines, and the NHS says people with a severe mental illness can have a physical check-up at their GP surgery once a year. Things that can interact with antipsychotics include some medicines, alcohol, illegal drugs and caffeine. Stopping smoking can increase the amount of antipsychotic in the blood, so a lower dose may be needed. Tell the prescriber before you start, stop or cut down on any of these.

Rethink highlights self-care and management skills, and says an NHS mental health team should support people to learn how to manage their symptoms. Family intervention is described as a recommended part of care.

The NHS says that if someone is in immediate danger, or has made an attempt to harm themselves, call 999. If you feel suicidal you can call Samaritans on 116 123, go to A&E, contact NHS 111, or make an urgent appointment with a GP or psychiatrist or care team. A local NHS crisis team can also support someone who is becoming rapidly more unwell, and NHS 111 can give urgent mental health advice and refer you on.

Catatonia, where a person is very still, unresponsive or agitated, is described by the College as extremely serious and something that should be treated quickly.

Most care is provided free through NHS community mental health teams, Early Intervention in Psychosis teams and, when needed, crisis and inpatient services. Rethink says NICE advises that EIP services should be open to people of all ages and that treatment should start within 2 weeks of referral, and that you can usually self-refer to your local EIP team without first seeing a GP. The College points out that some services are not available across the whole UK and may not be accessible straight away.

Some people also choose to see a private consultant psychiatrist for an assessment or second opinion. It is still sensible to keep the GP and NHS team informed so that physical health monitoring, prescribing and crisis planning stay with one joined-up team.